What is Character LCD Display and Graphic LCD Display? There are many people do not understand what is the meaning. Then also do not know how to start, and sometimes blindly to contact, and then lead to unnecessary trouble, but do not have to worry, Sinocrystal will introduce you what is Character LCD Display & Graphic LCD Display, so that you can understand more about this aspect of the content, and I believe you will have a harvest after reading!
LCD module is a liquid crystal display device, connections, integrated circuits, PCB circuit boards, backlight, structural components assembled together components. The English name is «LCD Module», referred to as «LCM».
In fact, it is a kind of commercialized components. According to the relevant national standards in China: only the non-detachable integrated parts are called «modules», and the detachable ones are called «components». So the standard call should be called «liquid crystal display components». But since a long time people have been accustomed to call it «module».
In a broad sense, all the components assembled together by the LCD device and integrated circuit belong to the «module», but in fact we usually say «module» mainly refers to the dot matrix LCD device assembly of the dot matrix LCD module, especially because it is a dot matrix Liquid crystal display device products in addition to some special high-volume varieties (such as translation machines, communications with), the manufacturer is directly to the user supply LCD devices, almost all general-purpose dot matrix LCD devices are processed into modules before supplying the user, so it is easy to form «LCD module» is «dot matrix LCD module» misunderstanding.
First: Dot matrix Character LCD Module
It is by the dot matrix character LCD devices and special line, column driver, controller and the necessary connections, structural components assembled from, can display digital and Western characters. This kind of dot matrix character module itself has character generator, large display capacity and rich functions.
Generally this kind of module can also display at least 8-bit 1 line or 16-bit l line or more characters. The dot matrix arrangement of this module is composed of a group of 5×7, 5×8 or 5×11 pixel matrix arrangement. Each group is 1 bit, and there is a bit of interval between each bit and a line of interval between each line, so it cannot display graphics, and its specifications are mainly shown in the following table.
8 bits
1 line;2 lines
16 bits
1 line;2 lines;4 lines
20-bit
1 row;2 rows;4 rows
24-bit
1 line;2 lines;4 lines
32-bit
1 line;2 lines;4 lines
40 bit
1 line;2 lines;4 lines
Generally in the module control, the driver has been solidified in the 192 character font CGROM character library, but also has a user-defined to build a special character random memory CGRAM, allowing users to build eight 5 × 8 dot matrix characters.
Second: dot matrix graphic LCD module
This kind of module is also a kind of dot matrix module, which is characterized by continuous arrangement of dot matrix pixels, with no empty space in both rows and columns in the layout. Therefore, a continuous and complete graphic can be displayed. Since it is also composed of X-Y matrix pixels, it can also display characters in addition to graphics.
- Row and column driver type This is a kind of module that must be connected to a special controller, and its module is only assembled with general-purpose row and column drivers, which actually only have general drive outputs for pixels, while the inputs generally only have data inputs below 4 bits, shift signal inputs, latch inputs, AC signal inputs, etc., such as HD44100, IID66100, etc.
This type of module must be connected to an external control circuit, such as HD61830, SEDl330, etc. in order to connect to the computer. This type of module is the most numerous and most common. Although it needs to use its own controller, but it also leaves the customer the freedom to choose different controllers.
- Row and column drive-control type
This is a module that can be directly interfaced with a computer and relies on the computer to directly control the drive. The column driver used in this type of module has an I/O bus data interface, so the module can be directly hooked up to the computer’s bus, eliminating the need for a dedicated controller, and therefore is beneficial to the overall system cost reduction. It is very suitable for users who do not have a large number of pixels, do not have many functions in the whole machine, and are familiar with the programming of computer software. However, it will take up some of your system’s resources.
- Row and column control type
This is a type of dot matrix graphics module with built-in controller. It is also one of the more popular types. This type of module is not only equipped with row and column drivers such as the first type, but also equipped with special controllers such as T6963C.
This controller is the interface between the LCD driver and the computer, it is controlled by the computer in the simplest way, receives and feeds back various information from the computer, realizes the management of the display buffer through its own independent information processing, provides the driver with various signals and pulses needed to manipulate the driver to achieve the display function of the module.
This controller has its own set of special instructions and has its own character generator CGROM. Users must be familiar with the detailed instructions of this controller in order to carry out a summary. This kind of module makes the user get rid of a series of work on the design, processing and production of the controller, and also makes the computer avoid the tedious control of the display, saving the internal resources of the host system.
The above for you to introduce the character LCD and graphics LCD, if you are interested and want to understand this aspect, you can consult our official website, professionals will immediately communicate with you, to answer your questions!